铸机的弧形半径通常用铸坯内弧曲率半径表示。
参考答案：错
There aren’t enough chairs. Would you please ______ ones here?[ ]
A. to bring another three
B. bring more three
C. to take three other
D. bring three more
Ag（DDC）法需用有机碱吸收反应中的（）
A.砷化氢
B.吡啶溶液
C.二乙基二硫代氨基甲酸
D.三乙胺-氯仿
E.砷溶液
